Vaccinium corymbosum L. plant named &#39;RYOKU NH-12&#39;

ABSTRACT

A new and distinct variety of  Vaccinium corymbosum  L. plant named ‘RYOKU NH-12’, characterized by having more compact plant size, comparatively early fruit ripening time, comparatively large and uniform fruit size, firmer and lower dehiscent fruits, sweeter fruits, better taste balance of sweetness and acidity, and better taste of fruits, as compared to other  Vaccinium corymbosum  L. varieties.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Japanese Plant Breeders' Rights Application No. 31724, filed Jan. 4, 2017, the contents of which are incorporated herein by reference in their entirety.

The Latin name of the genus and species of the novel variety disclosed herein is: Vaccinium corymbosum L.

The novel variety of the Vaccinium corymbosum L. disclosed herein has been given the variety denomination: ‘RYOKU NH-12’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct hybrid variety of northern highbush blueberry (Vaccinium corymbosum L.) named ‘RYOKU NH-12’. This novel variety was found by open pollination of ‘Spartan’, ‘Duke’ and ‘Denies Blue’ in the tests conducted for the period from 2004 to 2008 in Matsumoto-City, Nagano-prefecture, Japan. As stated below, ‘RYOKU NH-12’ has apparently different characteristics from those of the ‘Spartan’ and ‘Duke,’ both being widely planted and important varieties in the Chubu district of Japan.

SUMMARY OF THE INVENTION

Blueberry variety ‘RYOKU NH-12’ exhibits outstanding and distinguishing characteristics when grown under normal horticultural conditions in the area from Nagano-prefecture to the north of the Kanto in Japan, including:

-   -   (1) more compact plant size;     -   (2) comparatively early fruit ripening time (50% fruit ripening         around late June of each year in Matsumoto, Nagano, Japan);     -   (3) comparatively large and uniform fruit size;     -   (4) firmer and lower dehiscent fruits;     -   (5) sweeter fruits with better taste balance of sweetness and         acidity; and     -   (6) better taste of fruits.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying colored photographs (FIGS. 1 to 8) show typical bush, flower, fruit and leaf characteristics of the new Vaccinium corymbosum L. plant, ‘RYOKU NH-12’. Colors shown are as accurate as can be reasonably reproduced by photographic means. In some cases, the color might differ slightly from the colors of ‘RYOKU NH-12’ recited in the description.

FIG. 1 shows a tree body of ‘RYOKU NH-12’ (photographed date: Jul. 9, 2014; photographed location: NIPPON RYOKUSAN CO., LTD, Matsumoto-City, Nagano-prefecture, Japan).

FIG. 2 shows a panoramic view of the cultivation area of ‘RYOKU NH-12’ (photographed date: Sep. 7, 2012; photographed location: same as FIG. 1).

FIG. 3 shows whole flowers of ‘RYOKU NH-12’ (photographed date: May 6, 2014; photographed location: same as FIG. 1).

FIG. 4 shows broken-down parts of a flower of ‘RYOKU NH-12’ (photographed date: May 6, 2014; photographed location: same as FIG. 1).

FIG. 5 shows fruits of ‘RYOKU NH-12’ (photographed date: Jul. 15, 2014; photographed location: same as FIG. 1).

FIG. 6 shows a cross-section of the fruits of ‘RYOKU NH-12’ (photographed date: Jul. 15, 2014; photographed location: same as FIG. 1).

FIG. 7 shows an upper side of the leaves (10 sheets) of ‘RYOKU NH-12’ (photographed date: Aug. 3, 2012; photographed location: same as FIG. 1).

FIG. 8 shows a lower side of the leaves (10 sheets) of ‘RYOKU NH-12’ (photographed date: Aug. 3, 2012; photographed location: same as FIG. 1).

DETAILED BOTANICAL DESCRIPTION A. Distinctive Characteristics of ‘RYOKU NY-12’

As described above, ‘RYOKU NH-12’ was obtained by the open pollination of ‘Spartan’, ‘Duke’ and ‘Denies Blue.’ On Apr. 15, 2004, about 1,000 seeds obtained from the mixed fruits of ‘Spartan’, ‘Duke’ and ‘Denies Blue,’ all of which were harvested in the field of NIPPON RYOKUSAN CO., LTD. (Matsumoto, Nagano, Japan), seeded in plant seeding trays, and then transplanted to pots. The resulting seedlings (about 300) were planted in cultivation pots on May 1, 2005. Fructification of the planted seedlings was started from Jun. 20, 2008 (on Year 3), and about 20 plant individuals were selected based on the characteristics, including larger fruit size, better taste balance of sweetness and acidity, higher yield per plant, earlier ripening time, large and uniform fruits, etc. For the about 20 plant individuals selected, test plots (each including about 20 cuttings per plant individual) were formed, where these plants were asexually propagated by cutting means. During the period from Jul. 20, 2010 to Dec. 25, 2016 and for 3 generations, the plants were propagated and examined for their characteristics based on the growth, and yield and fruits quality in each test plot. For 10 test plots, the characteristics of the plants were observed for the period between the flowering time and the ripening time yearly for 4 years, and since neither variant nor off-type plant was observed for the period, the characterization of ‘RYOKU NH-12’ was finished on Dec. 25, 2016 and the breeding was completed.

‘RYOKU NH-12’ is a blueberry clone distinguishable from the important blueberry varieties ‘Spartan’ and ‘Duke’, both of which are widely planted in the Chubu district of Japan, due to its characteristics including more compact plant size, comparatively early fruit ripening time, comparatively large and uniform fruit size, firmer and lower dehiscent fruits, sweeter fruits with better taste balance of sweetness and acidity, and better taste fruits. 20 plants of ‘RYOKU NH-12’ had been propagated by cutting means in Matsumoto, Nagano, Japan, and all the resulting plants were phenotypically indistinguishable from the original plant variety ‘RYOKU NH-12’. In addition, comparing to ‘Spartan’ and ‘Duke’, the claimed plant ‘RYOKU NH-12’ has more compact plant size, about 1 week earlier fruit ripening time (on average, around June 25 to July 1 of each year in Matsumoto, Nagano, Japan), larger and more uniform fruit size, and firmer and sweeter fruit when compared to its related variety ‘Spartan’, and has more compact plant size, lower dehiscent fruits, sweeter fruits, a better balance of sweetness and acidity, and better tasting of fruits when compared to the ‘Duke’ variety (see Table 1 below).

The following data defining characteristics of ‘RYOKU NH-12’ were collected from the asexual propagation carried out in Matsumoto, Nagano, Japan. The plant history was taken on a plot of 10 four-year-old plants growing in Matsumoto, Nagano, Japan. ‘RYOKU NH-12’ has not been observed under all possible environmental conditions, and the measurements provided might therefore vary if grown in different environments. Where averages are given, the sample size was 10.

B. Phenotypic Description of Vaccinium corymbosum L. (‘RYOKU NH-12’)

Characteristics of ‘RYOKU NH-12’ are further specifically described as follows:

-   1. Plant:     -   -   Plant vigor.—Medium.         -   Growth habit.—Semi-upright.         -   Plant size.—Small.         -   Plant height.—1.3 m on average for 4-year old plant.         -   Plant spread.—0.8 m on average for 4-year old plant.         -   Cold hardiness.—Survived in winter frost (below —10° C.)             with minimum damage.         -   Ease of propagation.—Propagated from each of the dormant             wood cutting and the softwood stem cutting, where the             rooting percentage was greater than 70% and comparable to             the other varieties. -   2. Trunk and branches:     -   -   Suckering tendency.—Medium suckering tendency.         -   Surface texture (of 6-month-old shoots).—Medium smoothness.         -   Surface texture (of 3-year-old and older wood).—Medium             smoothness.         -   Color of new twigs observed in the field.—Orangish yellow             green.         -   Internode length.—16.2 mm on average. -   3. Leaves:     -   -   Length including petiole.—54.0 mm on average.         -   Width of leaf at widest point.—33.0 mm on average.         -   Shape.—Ovate.         -   Leaf margin.—Entire.         -   Color.—Upper surface: Medium Green.         -   Pubescence.—Upper Surface of leaves: Absent. Lower Surface             of leaves: Absent. Margin: Absent.         -   Timing of vegetative bud burst.—Medium. -   4. Flowers:     -   -   Shape.—Campanulate.         -   Flowering period.—Mean date of 50% opening of flowers in             Matsumoto-City, Nagano-prefecture, Japan is May 1 (2 days             earlier than ‘Spartan’ variety).         -   Corolla.—Diameter: 7.4 mm on average. Length (from pedicel             attachment point to corolla tip excluding the pedicel): 10.8             mm on average. Color: light green white. Anthocyanin             coloration in corolla tube — Absent or very weak. -   5. Reproductive organs:     -   -   Pollen.—Color: Yellow. -   6. Fruit:     -   -   Mean date of 50% harvest in Matsumoto-City,             Nagano-prefecture.—July 1 on average.         -   Diameter of calyx aperture on mature berry.—5.9 mm on             average.         -   Size and shape of calyx lobe on mature berry.—Medium in             size, outcurving, and having deep calyx basin.         -   Detachment force for ripe berries (easy, medium,             hard).—Easy.         -   Fruit cluster density (sparse, medium, dense).—Medium.         -   Fruiting type.—On one-year old shoots only. -   7. Berry:     -   -   Cluster (tight, medium, loose).—Medium.         -   Weight (on well-pruned plants).—3.79 g on average.         -   Height.—14.9 mm on average.         -   Width.—20.4 mm on average.         -   Shape.—Oblate.         -   Surface color of mature berries ripe on the plant.—Blue             purple.         -   Intensity of fruit bloom.—Medium.         -   Surface color of ripe berry after polishing.—Medium blue.         -   Immature berry color, with bloom.—Medium green.         -   Immature berry color, without bloom.—Yellow green.         -   Flesh color.—White.         -   Peel color.—Medium blue.         -   Pedicel scar.—Medium. 2.92 mm on average.         -   Firmness.—Medium.         -   Intensity of fruit sweetness.—High, Bx 14.5.         -   Intensity of fruit acidity.—High, pH 2.59.         -   Texture.—Somewhat soft pulp, very juicy, medium seeds. -   8. Use: ‘RYOKU NH-12’ produce northern highbush blueberries suitable     for fruit-picking farms, fresh fruit markets and processed fruit     market, etc. -   9. Resistance to disease, insects, and mites: ‘RYOKU NH-12’ grew     vigorously and showed excellent bush survival in the field. It     appears to be tolerant to stem blight (Botryosphaeria spp.) and root     rot (Phytophthora cinnamoni), with very few young plants dying soon     after planting. The response of ‘RYOKU NH-12’ to the various fungal     species that cause summer leaf spots is typical of other northern     highbush varieties, and fungicide applications may be needed after     harvest in order to reduce foliar diseases and to retain leaves     until autumn and make maximum flower bud set. Similarly,     susceptibility to typical blueberry insect and mite pathogens, such     as spotted wing drosophila (Drosophila suzukii), blueberry gall     midge (Dasineura oxycoccana) and blueberry bud mite (Acalitus     vaccini), is similar to other northern highbush cultivars.

TABLE 1 (Comparison of characteristics among varieties) The present Control Char- Standard variety act. UPOV Variety RYOKU Varieties No. No. Code Characteristics Definition Method Class State (Ex. Var.) NH-12 Spartan Duke  1  1 QN Plant: vigor Stength of growth Observa- 3 weak Bluetta, (*) (+) level of plant tion Meader (a) 5 medium Collins, VG Weymouth 5 6 7 7 strong Berkeley, Homebell, Woodward  2 QN Plant: size Size of plant crown Observa- 3 small Avonblue, tion Bluetta, (a) Flordablue VG 5 medium Bluecrop, 3 5 7 Earliblue 7 large Dixi, Homebell, Tifblue  3  2 QN Plant: growth habit Whole shape of Observa- 1 upright Becyblue, (*) G plant without tion Bluechip, pruning during (a) June, dormant period VG Spartan 2 1 1 2 semi-upright Bluecrop, Lateblue 3 spreading Northland, Weymouth  4  3 PQ One-year-old Color of middle Observa- 1 green shoot: color part of shoot tion 2 greenish red extended before (a) 3 greyish red Briteblue, dormant period VG Homebell 4 reddish yellow Berkeley, 5 4 4 Dixi 5 reddish brown Blueray, Darrow, Weymouth 6 dark red  5 QN One-year-old Length of middle Measure- 3 short shoot: length part of shoot ment 5 medium 5 7 7 extended before mm 7 long (164 (222 (245 domant period (a) mm) mm) mm) VG  6  4 QN One-year-old Length of Observa- 3 short Avonblue, shoot: length internode of shoot tion Weymouth of internode extended before (a) 5 medium 4 5 5 (upper half) dormant period VG 7 long Jersey (16.2 (17.0 (18.0 (upper half) mm) mm) mm)  7  5 QN Leaf: length Length of leaf Measure- 3 short (*) sufficiently 5 medium expanded mmment 7 long 3 5 5 (b) (54.0 (76.0 (71.0 MS/ mm) mm) mm) VG  8  6 QN Leaf: width Maximum width of Measure- 3 narrow mature leaf ment 5 medium 5 5 5 mm 7 broad (33.0 (37.0 (36.0 (b) mm) mm) MS/ mm) VG  9  7 QN Leaf: ratio length/ Ratio of leaf length to Measure- 3 small width maximum width ment 5 medium 4 5 5 (leaf length/ (b) 7 large (1.64) (2.05) (1.97) leaf width) MS/ VG 10  8 PQ Leaf: shape Shape of mature leaf Observa- 1 lanceolate (*) tion 2 ovate Northland (b) 3 elliptic Berkeley, 2 3 3 VG Collins, Coville 4 oblong 11 QN Leaf: shape of tip Shape of tip of Observa- 3 acute Weymouth, (+) mature leaf tion Woodard (b) 5 medium Earliblue, VG Tifblue 5 6 5 7 obtude Berkeley, Climax, Southland 12  9 QL Leaf: color Color of surface of Observa- 1 yellow of upper mature leaf tion 2 green Bluechip, 2 2 2 side (b) Bluecrop, VG Blueray 13 10 QN Only varieties Intensity of green Observa- 3 light (*) with green leaf color on surface of tion 5 medium color: Leaf: mature leaf (b) 7 dark intensity of VG 5 7 7 green color on upper side 14 11 QL Leaf: margin Type of margin of Observa- 1 entire (*) mature leaf tion 2 serrate 1 1 1 (b) VG 15 12 QN Flower bud: Intensity of Observa- 3 weak anthocyanin antocyanin tion 5 medium coloration coloration of flower (b) 7 strong 5 5 5 bud occurring to one VG year old shoot 16 13 QN Inflorescence: Length of Measure- 3 short length inflorescence at ment 5 medium (excluding flowering time mm 7 long 7 5 5 peduncle) (excluding peduncle) (c) (35.7 (25.2 (26.4 MS/ mm) mm) mm) VG 17 14 PQ Flower: Shape of corolla at Observa- 1 urceolate Bluecrop, shape of full bloom tion Jersey corolla (c) 2 campanulate Northblue, 2 1-2 2 VG Northsky 3 cylindrical 18 PQ Flower: color of Color of corolla at full Observa- 1 white Aliceblue, corolla bloom tion Bluetta, (c) Briteblue VG 2 creamy white Avonblue, Berkeley, Bluerop 3 greenish white Blueray, 2 2-3 2-3 Collins, Coville 4 light pink BLuebell, Delite, Dixi, Tifblue 19 15 QN Flower: size of Size of corolla Observa- 3 small (*) corolla tube tube at full bloom tion 5 medium 5 5 6 (c) 7 large VG 20 16 QN Flower: Intensity of Observa- 1 absent or (*) anthocyanin anthocyanin tion very weak coloration of coloration on (c) 3 weak corolla tube surface of corolla VG 5 medium 1 1 3 tube 7 strong 21 17 QL Flower: Presence or absence Observa- 1 absent Herbert ridges on of ridges on corolla tion 9 present Aliceblue corolla tube tube (c) Berkeley, 9 9 9 VG Dixi 22 18 QN Fruit cluster: Density of fruit per Observa- 3 sparse Homebell, density fruit cluster tion Jersey, (d) Woodard VG 5 medium Bluechip, Bluecrop, 5 5 5 Bluetta 7 dense Darrow, Herbert, Patriot 23 19 QN Unripe fruit: Intensity of green Observa- 3 light (*) intensity of color of fruit before tion 5 medium 5 3 5 green color ripening VG 7 dark 24 20 QN Fruit size Size of fruit at Observa- 3 small Homebell, (*) ripening tion June, (d) Northblue VG 5 medium Collins, 7 7 7 Earliblue (3.79 g) (4.56 g) (3.96 g) 7 large Berkeley, Bluecrop, Spartan 25 21 PQ Fruit: shape in Shape in Observa- 1 elliptic (*) (+) longitudinal longitudinal tion 2 round Berkeley, section section of fruit at (d) Jersey, ripening VG Sharpblue 3 3 3 3 oblate Earliblue, Harison, Woodard 26 QN Fruit: size of scar Size of stem scar Observa- 3 small (+) of mature fruit tion 5 medium 5 5 5 (d) 7 large (2.92 (2.30 (1.90 VG 27 PQ Fruit: shape of Shape of calyx Observa- 1 star mm) mm) mm) (+) calyx cavity cavity of mature tion 2 circular 2 2 2 fruit (d) VG 28 22 QN Fruit: attitude of Attitude of sepals Observa- 1 erect sepals relative to mature tion 2 erect to fruit (d) semi-erect VG 3 semi-erect 2 1 1 4 level 29 23 QN Fruit: type of Direction of curving Observa- 1 incurving sepals of sepals tion 2 straight 3 1 3 (d) 3 reflexed VG 30 24 QN Fruit: diameter Diameter of calyx Observa- 3 small Avonblue, of calyx basin basin of mature fruit tion Bluechip, (d) Sharpblue VG 5 medium Blueray, 5 5 5 Woodard (5.86 (5.80 (5.90 7 large Coville, mm) mm) mm) Darrow, Homebell 31 25 QN Fruit: depth of Depth of calyx basin Observa- 3 shallow Bluecrop, calyx basin of mature fruit tion Rancocas, (d) Tifblue VG 5 medium Earliblue, 7 7 5 Jersey (2.72 (2.20 (1.50 7 deep Blueray, mm) mm) mm) Collins, Dixi 32 26 QN Fruit: Intensity of bloom Observa- 1 very weak (*) intensity on surface of tion 3 weak Dixi, of bloom mature fruit (d) Herbert, VG Sharpblue, 5 medium Collins, 5 5 5 Coville 7 strong Avonblue, Bluecrop, Tifblue 33 27 PQ Fruit: color of skin Color of skin of Observa- 1 light blue Berkeley, (*) G (after removal of mature fruit after tion BLuechip, bloom) removal of bloom (d) Tifblue VG 2 medium blue Blueray, Jersey, 2 2 2 June 3 dark blue Dixi, Homebell 4 blue red 34 28 QN Fruit: formness Formness of mature Observa- 3 soft Herbert, (+) fruit tion Homebell, (d) Spartan VG/ 5 medium Collins, VS Dixi, 5 3 5 7 firm Coville, Southland 9 very firm 35 PQ Fruit: color of Color of flesh of Observa- 1 white Berkeley, flesh mature fruit tion Bluecrop, (d) Blueray VG 2 cream Earliblue 3 light green Bluechip, 1 2-3 1-2 Lateblue, Sharpblue, 4 light purple Aliceblue, Delite, Homebell 36 29 QN Fruit: sweetness Sweetness of mature Observa- 3 low Avonblue, (*) (+) fruit tion Bluechip, (d) 5 medium Berkeley, VG Bluetta, 7 5 5 Spartan (Bx (Bx (Bx 7 high Alicblue, 14.5) 11.9) 11.1) Bluecrop, Blueray 37 30 QN Fruit: acidity Acidity of mature fruit Observa- 3 low Earliblue, (*) (+) tion Homebell (d) 5 medium Blueray, 7 5 3 VG Herbert (pH (pH (pH 7 high Collins, 2.59) 3.12) 3.87) Elliott, Lateblue 38 31 QL Plant: fruiting type Shhots to which fruit Observa- 1 on one-year-old (*) G adnate tion shoots only (c) 2 on one-year- 1 1 1 VG old and current season's shoots 39 QN Fruit: tendency of Tendency of Observa- 3 less Earliblue, cracking cracking during tion Herbert, harvest season (d) Spartan VG 5 medium Avonblue, Berkeley, 3 3 3 Bluechip 7 much Briteblue, Climax, Darrow 40 32 QN Time of Time to beginning to Measure- 3 early Avonblue, (*) (+) vegetative bud burst firstbegetative ment Beckyblue burst bud of each MG Sharpblue individual plant 5 medium Darrow, 5 7 5 Weymouth April 6 April 8 April 5 7 late Elliott, (2016) (2016) (2016) Lateblue 41 33 QN Time of beginning Time of 10% Measure- 1 very early (*) (+) of flowering on flowering occurring to ment 3 early G one-yearold shoot one year old shoot MG 5 medium Bluecrop, Collins, 3 3 3 Woodard April 25 April 24 April 24 7 late Dixi, (2016) (2016) (2016) Herbert, Lateblue 9 very late 42 34 QN Varieties which fruit Time of 10% Measure- 3 early (*) (+) on one-year-old flowering occurring to ment 5 medium G shoot and current current year's shoot MG 7 late season's shoot: Time of beginning — — — of flowering on current year's shoot 43 35 QN Time of beginning Time of 10% fruit Measure- 1 very early (+) of fruit ripening on ripening on one year ment 3 early Avonblue, G one-year-old shoot old shoot MG Earliblue, Weymouth 5 medium Herbert, 3 3 3 Jersey Around Around Around 7 late Briteblue, June 20 June 25 June 20 Elliott, Tifblue 9 very late 44 QN Period of harvest Length of harvest Measure- 3 short Darrow, period of fruit ment Northblue MG 5 medium Berkeley, Bluecrop 5 5 5 7 loing Briteblue, Tifblue, Woodard 45 36 QN Varieties which fruit Time of 10% fruit Measure- 3 early (*) (+) on one-year-old ripening on current ment 5 medium G shoot and current year's shoot MG 7 late season's shoot: Time of beginning — — — of ripening on current year's shoot 

What is claimed is:
 1. A new and distinct variety of Vaccinium corymbosum L. plant named ‘RYOKU NH-12’, as described and illustrated herein. 